Versatile bugs found under ocean crust

WASHINGTON - Scientists have stumbled upon life teeming with versatile bugs in the deepest layers of the ocean crust.

Some of these microbes, existing in temperatures near the boiling point of water, can crunch hydrocarbons and natural gas and store carbon.

“This is a new ecosystem that almost no one has ever explored,” said Martin Fisk, professor at the College of Oceanic and Atmospheric Sciences, Oregon State University in the US, reports the journal PLoS One.

“We expected some bacterial forms, but the long list of biological functions that are taking place so deep beneath the Earth is surprising,” Fisk said.

Oceanic crust covers about 70 percent of the surface of the Earth and its geology has been explored to some extent, according to an Oregon Statement.

But practically nothing is known about its biology - partly because it is difficult and expensive, and partly because most researchers had assumed not all that much was going on.

The ocean floor is generally composed of three levels, including a shallow layer of sediment; basalt formed from solidified magma; and an even deeper level of basalt that cooled more slowly and is called the “gabbro” layer, which forms the majority of ocean crust.

The gabbro layer doesn’t even begin until the crust is about two miles thick. Core samples were obtained from gabbro rock formations that were closer to the surface than usual because they had been uplifted and exposed by faulting.

A research expedition drilled more than 4,600 feet into this formation, into rock that was very deep and very old, and found a wide range of biological activity.

It now appears that microbes in the deep ocean crust have at least a genetic potential for carbon storage, the report said.